The only thing a vacuum operated petcock can do other than flow all the fuel the float bowl can handle...is to restrict flow and thus cause a lean condition.swodo said:03 Heritage seems to sporadically run rich.
Heard that HD has had problems with the vacuum petcock leaking (while the engine is running) and causing a rich condition. If this is common?
Replace with non vaccum Pingel or what other brand do you recommend?
They can leak...but then they dont allow any kind of flow to the bowl cause of the bad diaphram.03LowRider said:What if the vacuum diaphragm in the petcock is leaking allowing fuel to be sucked up by the vacuum line? I took mine apart a while back but I can’t remember it fuel can get to the plunger side of the diaphragm.